{
  "family": "uacme",
  "sample_count": 5,
  "category": "ransomware",
  "description": "HackTool:Win32/Uacme (often detected due to its inclusion in the open-source **UACMe** repository) is a powerful, publicly available framework designed to bypass Windows User Account Control (UAC). While developed for security research and penetration testing, UACMe is heavily weaponized by threat actors and integrated into sophisticated malware (like ransomware and advanced RATs). It allows a process running with standard user privileges to silently escalate to high (Administrator) privileges without prompting the user with the familiar 'Do you want to allow this app to make changes?' dialog box.<br><br><b>Understanding UAC Bypasses</b><br>To an end-user, a successful UAC bypass is invisible; the malware simply gains administrative rights without asking. For a SOC, detecting UACMe usage indicates that an attacker has already gained initial access (as a standard user) and is actively escalating their privileges to fully compromise the host. The UACMe project currently catalogs over 70 distinct methods for bypassing UAC, constantly adapting as Microsoft patches older vulnerabilities.<br><br><b>Execution and Escalation Mechanics</b><br>Threat actors embed specific UACMe methods into their droppers (`T1548.002`). The most common techniques involve exploiting auto-elevating Windows executables (binaries signed by Microsoft that silently elevate without a prompt). For example, the attacker might drop a malicious DLL (`T1574.002`) into a specific system folder and then launch an auto-elevating Windows tool (like `sysprep.exe` or `cliconfg.exe`). Because the Windows tool is trusted, UAC elevates it silently; the tool then unknowingly loads the attacker's malicious DLL (DLL Hijacking), granting the attacker's code full administrative rights. Other methods involve complex COM interface hijacking or modifying specific registry keys (`HKCU\\Software\\Classes`) that trusted binaries read during execution.<br><br><b>Indicators of Compromise & Impact</b><br>The impact is Local Privilege Escalation (LPE), giving the attacker full control to disable AV, install rootkits, or dump credentials. Host-based IoCs include EDR alerts for anomalous DLL loads by trusted system processes (e.g., `sysprep.exe` loading a DLL from a non-standard path). Monitoring for sudden modifications to `HKCU\\Software\\Classes\\mscfile\\shell\\open\\command` or similar registry keys is critical. EDR systems should also flag any process spawning a high-integrity command prompt (`cmd.exe`) without a corresponding interactive user session.",
  "cta": "Published by the SystemHelpdesk team.",
  "aliases": [],
  "enrichment_level": "expert-seo",
  "faq": [
    {
      "@type": "Question",
      "name": "What is Uacme and what threat category does it belong to?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Uacme is classified as a Ransomware. Documented across security telemetry, it is engineered to execute unauthorized operations, establish persistent footholds on target endpoints, and facilitate malicious campaigns targeting enterprise and individual environments."
      }
    },
    {
      "@type": "Question",
      "name": "How does Uacme establish persistence and evade defensive controls?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Uacme typically establishes persistence through registry run keys, scheduled tasks, or service installations, while evading signature-based antivirus solutions through code obfuscation, memory injection, or anti-analysis sandbox checks."
      }
    },
    {
      "@type": "Question",
      "name": "What are the essential incident response steps for mitigating a Uacme compromise?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Security teams responding to Uacme should immediately isolate affected endpoints from the network, perform memory triage to capture volatile forensic artifacts, audit registry and startup persistence mechanisms, revoke exposed user credentials, and restore systems from verified, clean backups."
      }
    },
    {
      "@type": "Question",
      "name": "What cryptographic algorithms and file targeting techniques does Uacme employ during execution?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Uacme typically leverages hybrid cryptographic architectures combining symmetric stream or block ciphers (such as AES-256 or ChaCha20) for rapid file encryption with asymmetric algorithms (such as RSA-2048 or Curve25519) to securely protect the session keys. It aggressively targets sensitive file extensions including corporate documents, databases, virtual disks, and backups while systematically executing commands to delete Volume Shadow Copies (vssadmin delete shadows /all /quiet) and disable system recovery options."
      }
    },
    {
      "@type": "Question",
      "name": "Are decryptors available for Uacme, and what is the recommended recovery procedure?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Decryption availability for Uacme depends on whether security researchers or law enforcement (such as the No More Ransom initiative) have recovered the master private keys or discovered flaws in its key generation routines. Victims should never pay the extortion demand, as payment fuels criminal operations without guaranteeing file restoration. The recommended recovery procedure entails isolating infected hosts, conducting forensic disk imaging, identifying the root access vector, and restoring validated systems from immutable offline backups."
      }
    }
  ],
  "faq_count": 5,
  "mitre_attack": [
    "T1574.002",
    "T1546.015",
    "T1548.002"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-06-09",
  "mitre_attack_detail": [
    {
      "id": "T1548.002",
      "name": "Abuse Elevation Control Mechanism: Bypass User Account Control",
      "tactic": "Privilege Escalation"
    },
    {
      "id": "T1574.002",
      "name": "Hijack Execution Flow: DLL Side-Loading (Used in many UAC bypasses)",
      "tactic": "Privilege Escalation"
    },
    {
      "id": "T1546.015",
      "name": "Event Triggered Execution: Component Object Model Hijacking",
      "tactic": "Privilege Escalation"
    }
  ],
  "containment_steps": [
    "Immediately isolate the endpoint; if a UAC bypass was successful, the attacker now has full administrative control over the machine.",
    "Assume local administrator credentials and LSA secrets have been compromised; initiate password resets and verify no new administrative accounts were created.",
    "Analyze EDR process trees to determine *which* specific auto-elevating binary was abused, and use that information to hunt for lateral movement across the network.",
    "Ensure the organization's Windows endpoints are fully patched, as Microsoft continually addresses the specific UAC bypass methods documented in the UACMe project."
  ],
  "what_to_avoid": [
    "Do not assume that standard user accounts are secure simply because they are not administrators; UAC bypasses specifically target this gap.",
    "Avoid lowering the UAC slider to 'Never Notify' in enterprise environments, as this effectively disables UAC and makes privilege escalation trivial for malware."
  ],
  "target_industries": [
    "Healthcare",
    "Critical Infrastructure",
    "Enterprise"
  ],
  "motivation": "Financial Extortion",
  "threat_actors": [
    "Unknown / Cybercriminal"
  ],
  "target_geographies": [
    "Global"
  ],
  "attack_stage": [
    "defense_evasion",
    "impact"
  ],
  "ecosystem": [
    "windows_pe"
  ],
  "is_emerging": false,
  "target_platforms": [
    "Windows 11",
    "Windows 10",
    "Windows Server 2022",
    "Windows Server 2019"
  ]
}